Late Breaking Abstract - Mammalian target of rapamycin orchestrates eosinophil development in bone marrow

Eosinophil infiltration is regarded as a hallmark in allergic airway inflammation, and blockade of eosinophil differentiation may be an effective approach in treatment of eosinophil-related disorders. Mammalian target of rapamycin (mTOR) is a vital modulator in cell growth control and related diseases, and we have recently shown that rapamycin could suppress eosinophil differentiation in allergic airway inflammation. Considering of its critical roles in haematopoiesis, we further investigated the role of mTOR in eosinophil differentiation in the context of asthmatic pathogenesis. In our project, bone marrow cells with specific knockout of mTOR exhibited an increased eosinophil differentiation in the presence of IL-5 (Fig 1 A-H). Moreover, myeloid specific knockout of mTOR further augmented the allergic airway inflammation in mice after allergen exposure (Fig 2 A-D). Ablation of mTOR in myeloid cells also resulted in an increased number of eosinophil lineage-committed progenitors (Eops) in allergic mice (Fig2 E-H). Collectively, our data uncover promoted effects of mTOR in regulation of eosinophil development.